1. Field of the Inventions
The present inventions relate to multiple-cylinder engines, and more particularly to engines having an operation control device which changes the number of deactivated cylinders.
2. Description of the Related Art
Some known planing-type water vehicles include systems which disable respective cylinders of their engines. For example, these systems can be used to prevent over-revolution of the engine of a planing-type vehicle when the vehicle is operating in a planing state. Such a system is described in Japanese Patent Document JP-A-2002-371875.
The over-revolution state does not occur frequently in the engine of an ordinary automobile. However, because a water inlet opening for a jet pump of a planing-type water vehicle can rise out of the water and be exposed to the air, the jet pump can suck air in and relatively often cause the over-revolution state of the associated engine.